A pedometer generally includes a main body, an acceleration sensor provided in the main body for detecting a pace signal according to motion of the body, and a pace counter for counting the number of paces according to an output of the acceleration sensor. The number of paces is counted from the (up and down) movement of the body during walking (or running).
In detecting the up and down motion, the upward movement and the downward movement respectively vary greatly depending upon the state of the walking site, the shoes worn, the manner of walking, and the like. Therefore, there is a problem that the number of paces cannot be counted accurately in a conventional pedometer that counts the number of paces by detecting only the output corresponding to either the upward movement or the downward movement.
In order to solve this problem, the "pedometer" described in Japanese Patent Laying-Open No. 2-161932 (referred to as first prior art hereinafter), for example, includes an upper detector and a lower detector for detecting the upward acceleration and downward acceleration, respectively, and a select unit for selecting which of the pace signals from the upper or lower detector is to be the object of counting. It is aimed to count the number of paces accurately independent of the walking site, the shoes, and the manner of walking.
The pedometer described in Japanese Patent Laying-Open No. 1-287417 (referred to as second prior art hereinafter) employs a piezo-electric element formed in a cantilever structure as a sensor. A weight is provided at the free end of this sensor. An acceleration sensor having the fixed end supported via a shock elimination member is employed.
However, all the conventional pedometers including the one described in the first prior art has the main body of the pedometer in which an acceleration sensor is incorporated attached to the belt and the like of the pants or skirt to count the number of paces. There was a problem that the main body cannot be attached to one dressed without any belt and the like so that the number of paces cannot be counted. In the case where the main body is attached to the belt, the pedometer is noticeable since it has a size and thickness of some level. Others can easily perceive that the wearer is counting his/her number of paces. Even if the pedometer is covered by the clothing, the portion of the pedometer will bulge out to degrade the appearance. There was a problem that the style is spoiled.
The pedometer described in the above second prior art must have the weight and the piezo-electric element mounted in a weight case. There was a problem that assembly thereof is difficult, and the working cost increased. Furthermore, in the case where detection in a plurality of directions of virtual axes is required, the same acceleration sensor must be arranged individually at each direction of axis. There was a problem that the cost is increased.
The present invention is directed to these problems, and has an object of providing a pedometer that can count the number of paces without having to be attached to the belt, and that can easily be assembled and reduced in cost.
Another object of the present invention is to provide a pedometer that can accurately detect the number of paces and the like independent of the orientation of the main body.
A further object of the present invention is to provide an angle detection sensor of high accuracy with a broad application, and an angle detection device including such an angle detection sensor.